Q. How would I find out information about when animals are placed on an endangered animal list?

In the U.S. The Endangered Species Act of 1973 established the Endangered Species List.  This list is maintained nationally by two separate agencies.

The first is the U.S. Fish and Wildlife Service, they cover most land-based and freshwater species - think bass, birds, and 4-legged animals.

The second is the The National Marine Fisheries Service.

The NMFS is part of the National Oceanic and Atmospheric Administration (NOAA) and serves conservation needs related to ocean-going species (like whales and tuna)

Here's a breakdown of how each agency considers adding a species to the list, provided by the National Wildlife Federation:

How does a species get on the Endangered Species List?

When the U.S. Fish and Wildlife Service or the National Marine Fisheries Service is investigating the health of a species, they look at scientific data collected by local, state and national scientists. 

Whether or not a species is listed as endangered or threatened then depends on a number of factors, including the urgency and whether adequate protections exist through other means.

When deciding whether a species should be added to the Endangered Species List, the following criteria are evaluated:

• Has a large percentage of the species vital habitat been degraded or destroyed?
• Has the species been over-consumed by commercial, recreational, scientific or educational uses?
• Is the species threatened by disease or predation?
• Do current regulations or legislations inadequately protect the species?
• Are there other manmade factors that threaten the long-term survival of the species?

You can read more about it on the National Wildlife Federation's website on the Endangered Species Act.